what names do you mean: the Person Tag, Author, Copyright?
From my point of view these tags are already sorted.
E.g. "James Bond" is a plain text and nobody knows what is the first and the surname ;-), Also in Germany there are many names like "Martin Fritz" and both can be first name and surname.
If you want to sort by surname e.g. the Person Tag, I suggest to enter the surname "Bond" and then as a tag inside "Bond" the first name "James"
Now the tags are sorted by the surnames in the People Tag. The same with the other Tags.
If you don't want to have the hierarchy you should enter e.g. "Bond; James". You can't use the comma as separator (or you deactivate it in the window) because it separates multiple values and you would get two tags "Bond" and "James".